Validation of the Sysmex XN-V hematology analyzer for canine specimens

Abstract

Background: The Sysmex XN-V is derived from the new Sysmex XN series of human hematology analyzers. The main changes from the previously validated XT-2000iV analyzer include an optic-fluorescent analysis for platelets and nucleated RBC count.

Objective: We aimed to validate the Sysmex XN-V for canine blood according to American College for Veterinary Clinical Pathology and International Council for Standardization in Hematology recommendations.

Materials and methods: Canine EDTA blood specimens and quality control material were analyzed on the Sysmex XN-V to evaluate imprecision, bias, linearity, a comparison with the XT-2000iV analyzer, interference effects, carry-over, and stability. We also verified previously established Sysmex XT-2000iV reference intervals (RIs).

Results: Imprecision and bias were low (<5%) for most variables. Observed total error was lower than allowable total error for most measured variables except lymphocytes and monocytes. Visually determined linearity was excellent for all variables, except for lymphocytes. The correlation between the XN-V and XT-2000iV analyzers was high (>0.93) for all variables except MCHC and reticulocyte indices. Correlations between the Sysmex XN-V and manual differential counts were good for neutrophils and eosinophils, acceptable for lymphocytes, and fair for monocytes. Hemolysis, lipemia, and to a lesser extent icterus, had significant effects on measured hemoglobin concentration and associated variables. Carry-over was not visually observed for any variable. Changes in the Sysmex XN-V measurements after storage at 4℃ and 24℃ were similar to those described for the Sysmex XT-2000iV analyzer. The previously established Sysmex XT-2000iV RIs can be used to interpret results from the Sysmex XN-V analyzer for most variables except red blood cell distribution width and mean platelet volume.

Conclusions: The performance of the Sysmex XN-V analyzer was excellent and compared favorably with the Sysmex XT-2000iV analyzer.

Keywords: blood; comparison study; dog; method validation.